I use DMA IP on zedboard, I USE SG mode .I want to transfer data continuously via S2MM .I want to read data in the first descriptor while PL transfer data to second or third descriptor ! I alloc three buffers (three descriptors) to form a scatter list . now ,my question is ,when one descriptor's buffer have commplete .how it inform user application? so I can read the data in the first buffer,then modify the tail descriptor to next descriptor ! thanks a lot!
I know the descriptor have a complete bit in S2MM status , that need user application to inquire ,so it is not good real-time ,also the DMA generate a interrupt when the package finished ,so I want to know, how DMA can give user application a signal that one descriptor have compete,thanks!!!
I use DMA driver xilinx_axidma.c , the attachment is my DMA IP driver !